Present day electronic devices process and generate substantial amounts of data, and are able to deliver data generated by the devices themselves as well as data sensed and processed by the devices. Data is typically delivered to users in the form of visual displays, and is also frequently delivered audibly. Visual displays are naturally of little value to visually impaired users, particularly users who are severely visually impaired, and audible displays are similarly of little value to hearing-impaired users. In addition, displays of electronic devices must frequently compete with many other visual and audible stimuli, even for users with normal sight and hearing. Considerable efforts have been made to provide visual information to visually impaired persons, and it is easy to understand how the lives of such persons might be improved by technology that could let them see the world around them. Devices that stimulate the visual cortex and the optic nerve typically involve implants or other invasive techniques.